The present inventors have previously provided a flaky pigment in which the surfaces of fine flaky grains, as a pigment base, have been coated with barium sulfate grains, as an extender pigment for face powder which has excellent adhesiveness to the skin and excellent masking power to give desired gloss and transparency when applied to the skin (Japanese Patent Publication Nos. 2-42387 and 2-42388, corresponding to U.S. Pat. No. 4,603,047).
In the above-mentioned flaky pigment, the grain size of the barium sulfate grains to be deposited on the surfaces of the base pigment grains is large, i.e., from 0.5 to 2.0 .mu.m as a mean grain size. Therefore, the adhesiveness of the flaky pigment to the skin is not sufficient. It would be desirable for an extender pigment in face powder to have a wrinkle-masking effect due to scattering of light thereon, but the effect of the prior art flaky pigment is insufficient.
Japanese Patient Application Laid-Open No. 61-123673 has disclosed "pearl luster pigment and method of preparing the same" in which barium sulfate has been deposited on the surfaces of mica grains. However, the published specification of the patent application does not mention the method of preparing the pigment. In accordance with a method where barium sulfate and fine mica powder are merely blended so as to deposit barium sulfate on the surfaces of mica grains, fine grains of barium sulfate could not be uniformly deposited on the surfaces of mica grains.
In the case of a titanium oxide-coated mica which is generally used as a pearl luster pigment, the refractive index (n) of titanium oxide is 2.52 while that of mica is 1.56 so that the difference in the refractive index between them is large. As compared with mica as coated with titanium oxide (n=2.52) or iron oxide (n=3.0) having a large refractive index, mica as coated with barium sulfate has a small difference in the refractive index between barium sulfate (n=1.64) and mica (n=1.56). In addition, since the refractive indices of barium sulfate and mica are almost the same as those of coating paints or plastics (polyethylene, n=1.51 to 1.54; acrylic resins, n - 1.50 to 1.57), the pigment of barium sulfate/mica could not display the pearl luster pigment gloss and chroma when it is incorporated into coating paints or plastics.